Conventionally, there has been a motor coil bobbin that has a tubular body part and outer flange parts provided at both ends of the body part. A coil part is wound on the outside of the coil bobbin and an iron core tooth is inserted in the coil bobbin. The tooth and the coil part are insulated from each other by the coil bobbin (refer to JP 2000-341888 A).
Both the outer flange parts are each formed in a vertically elongated rectangular shape of the same size when viewed in the axial direction of the body part, and the coil bobbin is supported on the shorter sides of both the outer flange parts.
However, since the coil bobbin is supported on the shorter sides of both the outer flange parts when winding the coil part around the coil bobbin and inserting the tooth into the coil bobbin, the coil bobbin of which a barycentric position is raised with the coil part wound therearound cannot maintain a stable posture. This has led to degraded assembling workability due to the possible occurrence of inclination or fall of the coil bobbin when the tooth is inserted.